Reflecting on the 10th anniversary of the largest energy blackout in the United States, two Washington state power system experts said major improvements to the power grid make that type of calamity a far smaller possibility.
On Aug. 4, 2003, a series of system outages left much of the northeast United States without power for at least two days. The blackout affected about 45 million people in eight states.
Jeff Dagle, an engineer with the Pacific Northwest National Laboratory, was asked to help prepare the official analysis of that blackout. He determined the causes were both human error and computer malfunction.
The problem started with a single utility in Ohio and its failure to respond in time to stop a cascade of mishaps that rippled through the network to other utilities nearby.
As the problem grew, about 500 generating stations in the United States and Canada shut down, including 16 nuclear power plants.
“The power grid is a very complicated system,” Dagle said. As such it’s not possible to prevent an outage of that scope from ever occurring again, he added.
As recently as September 2011, a large swath of Southern California, centered in San Diego, experienced a large blackout, Dagle said. The event left about 7 million customers without power.
“It’s much like an airplane crash,” he said. “You try to avoid them and analyze them carefully to prevent the same mistakes.”
Following 2003, utilities and system operators like the Bonneville Power Administration invested in advanced technology that analyzes the network in real time and quickly shares that data with other nearby utilities, Dagle said.
“The system now provides a much more accurate picture of what is going on,” he said.
A PNNL colleague of Dagle’s, Carl Imhoff, also was working in the Tri-Cities when the 2003 blackout occurred. He manages PNNL’s electricity infrastructure research area.
Imhoff said the 2003 outage was vast and unprecedented. But he wasn’t surprised by how it happened.
“What occurred was consistent with how the system was designed. The grid is based on a protection philosophy, and the key devices are built to shut down when something out of the ordinary happens,” Imhoff said.
What failed to happen was human intervention by utility operators or network managers, who, early in the event, could have diverted power or shut down sections of the grid and stopped the impact, Imhoff said.
Like Dagle, Imhoff believes the power grid should increasingly rely on automated controls, coupled with human management. Humans still need to be at the controls, he said.
Imhoff won’t promise a massive blackout won’t happen again, either.
“What I do believe is that new technologies put in place over the last decade have significantly improved the ability of operators to avoid blackouts and recover more quickly from those that do occur.”